Containers comprising a spout for dispensing a liquid are well known in the art, especially in the field of dishwashing cleaning products. These bottles have an opening located at the top and are typically referred to as “top-up bottles”. In order to dispense the liquid, a consumer typically needs to open a cap to expose the spout, then invert and squeeze the bottle to dispense the liquid. Several problems exist with these top-up bottles. Firstly, the liquid flows out upon inversion of the bottle, even when the bottle is not squeezed making it difficult to control the amount of liquid to be dispensed from the bottle. This may also cause spillage of the liquid when the bottle is turned right side up after use. Secondly, these bottles appear messy as they tend to leave liquid around the rim of the spout. The liquid also tends to dry and forms a crust. If the crust is allowed to build up, then it eventually blocks the spout. Thirdly, the poor ergonomic design of these bottles causes consumer inconvenience. For example, constant twisting of the wrist to dose liquid from the top-up bottles can be uncomfortable or difficult on the consumers, especially with larger sized bottles and/or for the elderly consumers. Lastly, the presence of a closing cap or seal, which is needed to prevent solvent/other volatiles (e.g., perfumes) from evaporating, requires additional manipulations from the consumers making the bottles not user friendly. All these problems contribute to consumer dissatisfaction with these top-up bottles.
As a result, “inverted containers” have become popular with consumers. Inverted containers have an opening at the “bottom” for dispensing the liquid and are used in an upside-down position. The inverted containers typically rest on their bottom when placed on a horizontal surface. The inverted containers comprise a generally flexible bottle with a capped spout. An improvement to such a system may include a resilient valve in the discharge spout (see for example PCT WO2004/02843 (Method Products)). The aim of the valve is to help control the volume of liquid dispensed and minimize leakage with the inverted container so that liquid does not leak out unless force is applied to the containers.
A particular challenge with these types of inverted containers is the prevention of leakage of the liquid contained therein during steady state (i.e., storage) and/or upon impact, especially upon impact. For example, leakage may occur during storage when the inverted container is subjected to a temperature change, specifically increase (e.g., inverted container placed beside sunny window or near stove top, etc.), that can lead to internal pressure increases and leakage. Specifically, by “impact” it is meant that when the inverted container is handled, transported, dropped or knocked over. As a result of the impact, transient liquid pressure increases, also referred to as hydraulic hammer pressure, inside the container and can momentarily force open the valve causing liquid to leak out, which will result in consumer dissatisfaction with the product. Previous attempts to overcome the leakage problem have involved including a closing cap (see for example CN2784322U (Liu Zhonghai) & WO2014/130079 (Dow Global Technologies)). However, inclusion of a closing cap means additional steps of having to open the closing cap for dosing and reclose the closing cap after the dosing process, which is undesirable to consumers. Furthermore, the cap does not avoid liquid messiness and dried up crust of liquid around the spout/cap. Other attempts have incorporated baffles on top of the resilient valve (see for example JP2007/176594 (Lion), & WO2000/68038 (Aptar Group)), which have not completely resolved the leakage issue particularly as it pertains to inverted containers, more particularly upon impact.
Thus, the need remains for an improved liquid dispenser for an inverted container which substantially reduces or prevents the tendency of the valve to open when the inverted container is impacted, particularly dropped or knocked over. The need also exists for an improved liquid dispenser which reduces or prevents steady state leakage of the liquid. The need also exists for an improved liquid dispenser that accommodates the ease and/or accurate dispensing of the liquid. It is desirous that the improved liquid dispenser would greatly reduce or eliminate leakage so that the inverted container no longer requires a closing cap or seal. It is also desirous that the improved liquid dispenser has improve dispensing of the liquid with less residues, especially for sticky or high viscosity liquids. Further, it is desirous that the improved liquid dispenser accommodates inverted containers that have a variety of shapes and that are constructed from a variety of materials. The Applicant discovered that some or all of the above-mentioned needs can be at least partially fulfilled through the improved liquid dispenser as described herein below.